KR20250020329A - Substrate processing method - Google Patents

Abstract

A method for forming a low-k film by peald is provided. In one embodiment, a first silicon precursor is supplied to form a silicon precursor layer, and then a second silicon precursor is supplied. Then, an oxidizer is supplied to form a silicon oxide film. The method further includes a post-treatment to remove moisture from the film. The method according to the present disclosure enables forming a silicon oxide film having a desired low k value and excellent step coverage on a recessed structure.

Description

SUBSTRATE PROCESSING METHOD

The present disclosure relates to a method for forming a low-k film on a substrate, and more particularly, to a method for forming a low-k film in a recess by a plasma enhanced atomic layer deposition (PEALD) method.

As the critical dimension (CD) of semiconductor devices shrinks, electrical interference between material layers forming the circuit of the device increases. Electrical interference (e.g., electrical resistance) within the circuit causes RC (resistance-capacitance) delay from the insulating layer, which is one of the main causes of slow response time of semiconductor devices. To reduce the RC delay of the circuit, films with low k values (i.e., films with low dielectric constants) such as SiO, SiOC, and SiOCH have been introduced.

Low-k films are used as liner applications in TSV (Through Silicon Via) processes, where the low-k films are conformally thinly formed along the surface of a recessed region, such as a via, between metal layers formed. Low-k films having k values less than 3.9 are obtained by conventional plasma enhanced chemical vapor deposition (PECVD) methods. For example, SiO ₂ or SiN or a combination thereof can be used as a liner layer for low-k films. However, as the critical dimensions of semiconductor devices continue to shrink, the uniformity of the films deposited on the recessed structures deteriorates. For example, an overhang may occur at the upper portion of the recess during the PECVD process, which may result in the formation of a non-conformal film, which may adversely affect the k value (i.e., dielectric constant) of the film. In addition, as devices continue to shrink, films having lower k values (e.g., less than 3.5) are required.

Figure 1 illustrates film deposition along the surface of a recess by a conventional PECVD method. Figure 1 may be part of a TSV process, where a low-k film such as SiO ₂ or SiN may be formed as a liner on the walls of the recess, followed by formation of a barrier film such as Ta/TaN thereon, filling the recess with copper, and planarizing the substrate from the top and bottom of the substrate. In Figure 1, the PECVD process exhibits a high film growth rate, but non-conformal film deposition along the surface occurs (e.g., overhang in the upper region of the gap).

Therefore, it is necessary to conformally form a film with a low k value of 3.5 or less along the surface of the recessed structure.

The present disclosure discloses a method for forming films having not only low k values but also excellent step coverage characteristics along the gap structure in a narrow gap structure. Specifically, the present disclosure discloses a PEALD method for forming low-k films by supplying multiple precursors.

In one or more embodiments, a method for forming a low-k film comprises the steps of supplying a first silicon precursor to a reactor, supplying a second silicon precursor to the reactor, and supplying an oxidizer to the reactor. And the steps are repeated periodically a plurality of times to form a silicon oxide film.

In one or more embodiments, the first silicon precursor can include a reactive group including an alkylamine and a non-reactive group including an alkyl group and a hydrogen group, and the second silicon precursor can include a reactive group including an alkylamine and a non-reactive group including a hydrogen group.

In one or more embodiments, the first silicon precursor can be an organosilane-containing amine and the second silicon precursor can be an aminosilane.

In one or more embodiments, the first silicon precursor can include at least one of (dimethylamino)trimethylsilane, bis(dimethylamino)dimethylsilane, N,N-dimethyl-2,4,6,8-tetramethyl-cyclotetrasiloxan-2-amine, N,N-diethyl-2,4,6,8-tetramethyl-cyclotetrasiloxan-2-amine, or a combination thereof.

In one or more embodiments, the second precursor is DSMA, (SiH ₃ ) ₂ NMe; DSEA, (SiH ₃ ) ₂ NEt; DSIPA, (SiH ₃ ) ₂ N(iPr); DSTBA, (SiH ₃ ) ₂ N(tBu); DEAS, SiH ₃ NEt ₂ ; DTBAS, SiH ₃ N(tBu) ₂ ; BDEAS, SiH ₂ (NEt ₂ ) ₂ ; BDMAS, SiH ₂ (NMe ₂ ) ₂ ; BTBAS, SiH ₂ (NHtBu) ₂ ; DIPAS, SiH ₃ N(iPr) ₂ ; 3DMAS, SiH(N(Me) ₂ ) ₃ ; BEMAS, SiH ₂ [N(Et)(Me)] ₂ ; TEMS, SiH(NEtMe) ₃ ; TIPAS, SiH(NHiPr) ₃ ; BDIPADS, (N(iPr) ₂ )SiH ₂ -SiH ₂ (N(iPr) ₂ ); BDEADS, (NEt ₂ )SiH ₂ -SiH ₂ (NEt ₂ ); BDPADS, (NPr ₂ )SiH ₂ -SiH ₂ (NPr ₂ ); or at least one of a combination thereof.

In one or more embodiments, the oxidizer can include at least one of oxygen plasma, CO ₂ plasma, N ₂ O plasma, ozone, or a combination thereof.

In one or more embodiments, the method further comprises the step of supplying a hydrogen containing gas throughout the steps.

In one or more embodiments, the method further comprises performing a post-treatment to remove moisture from the silicon oxide film.

In one or more embodiments, the post-treatment can be performed by at least one of a plasma treatment, a UV treatment, a VUV treatment, or a combination thereof and a heat treatment.

In one or more embodiments, the plasma post-treatment can be performed by supplying at least one of argon plasma, helium plasma, hydrogen plasma, or a combination thereof.

In one or more embodiments, the dielectric constant of the silicon oxide film formed by the method can be 3.5 or less.

In one or more embodiments, the film growth rate of the silicon oxide film can be greater than or equal to 0.1 nm per cycle.

This Summary of the Invention is provided to introduce various concepts in a simplified form. These concepts are described in more detail in the detailed description of exemplary embodiments of the present disclosure below. This Summary of the Invention is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

Figure 1 illustrates film deposition along the surface of a recess by a conventional PECVD method.
Figure 2 illustrates a process flow for forming a low-k film using the method.
Figure 3 illustrates a timing graph for the process of Figure 2.
Figure 4 illustrates another process flow for forming a low-k film using the method.
Figure 5 shows a timing graph for the process of Figure 4.
Figure 6 illustrates the membrane formation mechanism according to the method.
Figure 7 shows the membrane structure before and after post-processing.
Figure 8 shows an FT-IR absorbance graph showing the film composition before post-treatment depending on the process conditions.
Figure 9 shows a TEM image of a low-k film formed on the sidewall of the gap in a TSV device using the method.
FIG. 10 illustrates a TSV process to which one embodiment of the present disclosure can be applied.
It will be appreciated that elements of the drawings are illustrated simply and clearly and are not necessarily drawn to scale. For example, the dimensions of some components in the drawings may be exaggerated relative to other components to help understand the implementations illustrated in the present disclosure.

While specific embodiments and examples are disclosed below, those skilled in the art will appreciate that the scope of the present invention extends to the specifically disclosed embodiments and/or uses of the present invention and obvious modifications and equivalents thereof. Accordingly, the scope of the disclosed invention should not be limited by the specific disclosed embodiments described below.

As used herein, the term "substrate" can refer to any underlying material or materials, including any underlying material or materials that can be deformed or upon which a device, circuit, or film can be formed. The "substrate" can be continuous or discontinuous; rigid or flexible; solid or porous; and combinations thereof. The substrate can be in any form, such as a powder, a plate, or a workpiece. A plate-shaped substrate can include wafers of various shapes and sizes. The substrate can be made of a semiconductor material, including, for example, silicon, silicon germanium, silicon oxide, gallium arsenide, gallium nitride, and silicon carbide.

The continuous substrate may extend beyond the boundaries of the process chamber in which the deposition process occurs. In some processes, the continuous substrate may be moved through the process chamber such that the process continues until the end of the substrate is reached. The continuous substrate may be supplied from a continuous substrate supply system to manufacture and output the continuous substrate in any suitable configuration.

The examples presented herein are not intended to be actual views of any particular materials, structures, or components, but are merely idealized representations used to illustrate embodiments of the present invention.

The specific applications shown and described are illustrative and best practice embodiments of the invention and are not intended to limit the scope of the embodiments and applications in any way. In fact, for the sake of brevity, conventional manufacturing, connection, preparation, and other functional aspects of the system may not be described in detail. Furthermore, the connecting lines shown in the various drawings are intended to represent exemplary functional relationships and/or physical connections between the various elements. Many alternative or additional functional relationships or physical connections may be present in a practical system and/or may be absent in some implementations.

Figure 2 illustrates a process flow for forming a low-k film using the method. Each step of the process flow will be described in more detail below.

In step 100 of FIG. 2, a substrate is provided within a reactor. The substrate may include a recessed structure, such as a gap, a 3D element structure, and a through hole penetrating the substrate. The substrate may be loaded onto a substrate support, such as a susceptor. The susceptor may be part of a heating block that supplies thermal energy to the susceptor.

In step 110, a first silicon precursor is supplied into the reactor. The first silicon precursor can be adsorbed onto a reaction site formed on a surface of the substrate. For example, the first silicon precursor can be conformally adsorbed on the surface along a gap structure.

The first silicon precursor can contain reactive groups including an alkylamine, and non-reactive groups including an alkyl group and a hydrogen group surrounding a silicon atom. For example, the first silicon precursor can contain an organosilane-containing amine group. More specifically, the first silicon precursor can be at least one of (dimethylamino)trimethylsilane, bis(dimethylamino)dimethylsilane, N,N-dimethyl-2,4,6,8-tetramethyl-cyclotetrasiloxan-2-amine, N,N-diethyl-2,4,6,8-tetramethyl-cyclotetrasiloxan-2-amine, or a combination thereof.

In step 120, a second silicon precursor is supplied into the reactor. The second silicon precursor may be adsorbed on the remaining reaction sites formed on the surface of the substrate but not occupied by the first silicon precursor. For example, the second silicon precursor may be conformally adsorbed on the surface along the gap structure.

The second silicon precursor can include a reactive group including an alkylamine and a non-reactive group including a hydrogen group surrounding the silicon atom. For example, the second silicon precursor can include an aminosilane. More specifically, the second silicon precursor can include DSMA, (SiH ₃ ) ₂ NMe; DSEA, (SiH ₃ ) ₂ NEt; DSIPA, (SiH ₃ ) ₂ N(iPr); DSTBA, (SiH ₃ ) ₂ N(tBu); DEAS, SiH ₃ NEt ₂ ; DTBAS, SiH ₃ N(tBu) ₂ ; BDEAS, SiH ₂ (NEt ₂ ) ₂ ; BDMAS, SiH ₂ (NMe ₂ ) ₂ ; BTBAS, SiH ₂ (NHtBu) ₂ ; DIPAS, SiH ₃ N(iPr) ₂ ; 3DMAS, SiH(N(Me) ₂ ) ₃ ; BEMAS, SiH ₂ [N(Et)(Me)] ₂ ; TEMS, SiH(NEtMe) ₃ ; TIPAS, SiH(NHiPr) ₃ ; BDIPADS, (N(iPr) ₂ )SiH ₂ -SiH ₂ (N(iPr) ₂ ); BDEADS, (NEt ₂ )SiH ₂ -SiH ₂ (NEt ₂ ); BDPADS, (NPr ₂ )SiH ₂ -SiH ₂ (NPr ₂ ), or at least one of a combination thereof.

After step 120, the film may include a silicon precursor layer including a first silicon precursor and a second silicon precursor. In steps 110 and 120, the non-reactive groups of the first silicon precursor and the non-reactive groups of the second silicon precursor may not participate in a chemical reaction between the first silicon precursor and the second silicon precursor to form the silicon precursor layer, so that pores may be formed in the silicon precursor layer. The generated pores may lower the k value of the silicon oxide film. Details of the reaction mechanism will be described later.

In step 130, an oxidizer is supplied into the reactor. The oxidizer can chemically react with the silicon precursor molecule layer formed in step 120 to form a silicon oxide film. The oxidizer can be an oxygen-containing gas activated by RF power applied in-situ or remotely to the reactor. The oxidizer can include at least one of oxygen plasma, CO ₂ plasma, N ₂ O plasma, ozone, or a combination thereof.

Steps 100 to 130 for forming a silicon oxide film can be performed at about 20° C. and about 100° C. or between about 35° C. and about 90° C., and an RF power of between about 30 W and about 200 W or between about 40 W and about 150 W can be applied to separate and activate the oxygen-containing gas.

In step 140, it is measured whether the target thickness of the silicon oxide film is achieved. If the target thickness is not achieved, steps 110 to 130 may be repeated. If the target thickness is achieved, the next step 140 is performed. The target thickness may be defined as a set thickness of the film to be formed on the wall of the recess.

Steps 110 to 130 can be repeated cyclically a plurality of times. A plurality of cycles can be input into a control system (e.g., software) of the substrate processing equipment. Whether the target thickness is achieved is determined by measuring whether the desired number of cycles is performed. The film growth rate of the silicon oxide film formed in steps 110 to 140 can be 0.1 nm or more per cycle.

Optionally, in step 150, a post-treatment can be performed. The post-treatment can remove reaction by-products, such as moisture, from the silicon oxide film. The post-treatment can be performed in-situ or ex-situ by at least one of a thermal treatment and/or a plasma treatment, a UV treatment, a VUV treatment (vacuum UV treatment), or a combination thereof. In one embodiment, the plasma post-treatment can be performed by supplying at least one of an argon plasma, a helium plasma, a hydrogen plasma, or a combination thereof at an RF power of less than or equal to 500 W applied between about 300° C. and about 500° C. or between about 350° C. and about 450° C. In another embodiment, in the plasma post-treatment, a radiofrequency plasma power can be applied to improve the treatment efficiency (i.e., more moisture can be removed). For example, a power of 10 MHz or greater can be applied.

At step 160, the process can be terminated and the substrate can be unloaded from the reactor. In another embodiment, steps 110 to 140 and step 150 can be performed externally. That is, steps 110 to 140 for forming a silicon oxide film can be performed in one reactor, and step 150 for post-treatment can be performed in another reactor.

Figure 3 illustrates a timing graph for the process of Figure 2. Each step will be described in more detail below.

Step T1 corresponds to step 110 of FIG. 2, where a first silicon precursor can be fed into the reactor.

Step T2 corresponds to step 120 of FIG. 2, where a second silicon precursor can be supplied into the reactor. The second silicon precursor can chemically react with the first silicon precursor to form a silicon precursor layer.

Step T4 corresponds to step 130 of FIG. 2, where an oxidizer is supplied. The oxidizer can chemically react with the silicon precursor layer, and a silicon oxide film can be formed.

Step T6 corresponds to step 150 of FIG. 2, where a post-treatment may be performed on the silicon oxide film. The post-treatment may be optionally performed. The post-treatment is to remove moisture from the silicon oxide film. In one embodiment, a plasma treatment may be performed as the post-treatment.

The purge step may additionally be performed after step T4 and before step T5, and after step T5. In another implementation, the purge step may be performed after step T1 and before step T2.

Steps T1 to T5 can be repeated a plurality of times until the silicon oxide film reaches a target thickness (i.e., full gapfill), and step T6 can be repeated a plurality of times.

Figure 4 illustrates another process flow for forming a low-k film using the method.

In FIG. 4, steps 200 to 260 are the same as in FIG. 2 except for step 270. Therefore, detailed descriptions of steps 200 to 260 will not be provided herein. In FIG. 4, a new step 270 is provided. In step 270, a hydrogen-containing gas is supplied to the reactor throughout steps 200 to 260. The hydrogen assists in the formation of -OH groups as bonding sites along the surface of the silicon precursor layer. Therefore, the step coverage of the feature and the film growth rate can be enhanced. The hydrogen-containing gas can be at least one of hydrogen, an acyclic hydrocarbon, or a combination thereof.

Figure 5 shows a timing graph for the process of Figure 4.

Figure 5 is similar to Figure 3, except that hydrogen is additionally supplied throughout the process. Hydrogen assists in the formation of bonding sites, such as -OH sites, along the surface of the silicon precursor layer, thereby enhancing step coverage in the gap structure.

Figure 6 illustrates the membrane formation mechanism according to the method.

In step 1 of FIG. 6, a first silicon precursor can be supplied to the substrate. The first silicon precursor can include an organosilane-containing amine group, which can contain a reactive group R1 and non-reactive groups R2 and R3. More specifically, the first silicon precursor can be at least one of (dimethylamino)trimethylsilane, bis(dimethylamino)dimethylsilane, N,N-dimethyl-2,4,6,8-tetramethyl-cyclotetrasiloxan-2-amine, N,N-diethyl-2,4,6,8-tetramethyl-cyclotetrasiloxan-2-amine, or a combination thereof.

The reactive group R1 may comprise an alkylamine, the non-reactive group R2 may comprise an alkyl group (e.g., -CH ₃ ), and the non-reactive group R3 may comprise a hydrogen group (e.g., -H) surrounding the silicon atom.

In step 1, Si-OH and Si-CH ₃ sites are already formed on the substrate from the previous cycle. The reactive group R1 of the first silicon precursor can react with -OH, and a Si-O-Si bond structure can be formed thereon, but does not react with -CH ₃ , and therefore a Si-O-Si bond structure may not be formed thereon.

In step 2, a second silicon precursor may be supplied to the substrate. The second silicon precursor may include an aminosilane containing a reactive group R1 and a non-reactive group R3.

The reactive group R1 may comprise an alkylamine, and the non-reactive group R3 may comprise a hydrogen group (e.g., -H) surrounding the silicon atom.

The reactive group R1 can react with the remaining -OH site formed on the substrate, and a Si-O-Si bond structure can be formed thereon. However, since there may be no reaction with the non-reactive group R2 (i.e., -CH ₃ ), the Si-O-Si bond structure may not be formed thereon. The space where the Si-O-Si bond structure is not formed may become a space that later causes a void, as shown in step 3.

In step 3, oxidation of the silicon precursor layer can be performed. The oxidation can be performed by supplying an oxidizer to the reactor. The oxidizer can be at least one of oxygen plasma, CO ₂ plasma, N ₂ O plasma, ozone, or a combination thereof. The plasma can be generated by supplying an RF power of between about 30 W and about 200 W or between about 40 W and about 150 W to the reactor. By supplying the oxidizer, the oxygen element can react with the non-reactive group R3 (i.e., -H) to form a -OH group. The -OH group can react with other -OH groups in the film to form a Si-O-Si network structure, and leave H ₂ O as a byproduct in the film as shown in the following chemical formula A.

[ - Si — H, H — Si - ] + oxidizing agent → - Si — O — Si - + H ₂ O (A)

Meanwhile, the -OH group that may not have another -OH group to react remains as an -OH site on the surface of the film as shown in the chemical formula B below and can act as a binding site (i.e., a reaction site) for the first silicon precursor in the next cycle.

[ - Si ― H ] + oxidizing agent → - Si ― OH (B)

Steps 1 to 3 can be performed at 100°C or less and repeated multiple times until the desired film thickness is achieved.

As described above, after the silicon oxide film is formed, pores are formed in the space where the non-reactive group R1(-CH ₃ ) exists, and therefore, the Si-O-Si bonding structure is not formed. In addition to the pores, moisture (i.e., H ₂ O) may be generated as a byproduct in the silicon oxide film according to the chemical formula A. Therefore, another step may be used to remove moisture therefrom.

In step 4, a post-treatment can be performed to remove moisture from the silicon oxide film. The post-treatment can be performed at a high temperature, for example, between about 300° C. and about 500° C. or between about 350° C. and about 450° C., to evaporate the moisture. In another embodiment, a plasma can be additionally provided to more effectively remove the moisture. The plasma can be at least one of argon plasma, helium plasma, hydrogen plasma, or a combination thereof. The plasma can bombard the silicon oxide film structure to destroy it, thereby facilitating more effective removal of moisture from the film. The plasma can be generated by applying an RF power of between about 200 W and about 600 W or between about 300 W and about 500 W to the reactor and activating a gas, such as argon, helium, hydrogen, or a combination thereof.

Figure 7 illustrates the membrane structure before and after post-treatment. As shown in Figure 7, after post-treatment, moisture is removed from the membrane and more pores are formed.

Figure 8 shows FT-IR absorbance graphs showing film compositions according to various silicon precursor supply sequences before post-processing.

In FIG. 8, four silicon precursor supply sequences are performed: supplying only the first silicon precursor (A), supplying only the second silicon precursor (B), supplying the first silicon precursor followed by the second silicon precursor (C), and supplying the second silicon precursor followed by the first silicon precursor (D).

As shown in Fig. 8, referring to sequence B and sequence D, the Si-CH ₃ peak (non-reactive group R2) is not detected. That is, the non-reactive group R2 was not detected in the potential space to form a void, which means that the space was filled and no void was formed.

Meanwhile, referring to sequence A and sequence C, Si-CH ₃ peak (non-reactive group R2) is detected. That is, a space where a pore can be formed can be formed, and thus, a pore can be generated accordingly. More specifically, sequence C (i.e., supplying a first silicon precursor followed by supplying a second precursor) shows the highest Si-CH ₃ peak intensity. That is, more pores can be generated by sequence C than by sequence A. Therefore, there is a technical advantage that a lower k value can be achieved by using sequence C (i.e., supplying a first silicon precursor followed by supplying a second precursor) as described in the present disclosure.

Table 1 shows the film characteristics of the SiO ₂ film formed according to the present disclosure. In Table 1, the silicon oxide film is conformally formed along the surface of the gap structure, with a width of 5.2 μm and a depth of 52 μm. The dielectric constant (k value) is about 3.5, reaching the target k value of 3.5 or less. As described above, the post-treatment removes moisture from the film, thereby enabling more pores to be formed. Therefore, performing the post-treatment has a technical advantage of lowering the k value. The test results show that the step coverage is 94%, achieving the target.

Film properties of SiO ₂ films formed according to the present disclosure test target Dielectric constant (k value) About 3.5 <3.5 Step Coverage (%)
(width 5.2um, depth 52um) 94 >90 growth rate (nm/cycle) 0.13 >0.1

Table 1 also shows that the film growth rate is more than 0.1 nm. Therefore, supplying dual precursors has a technical advantage that can improve the film growth rate and throughput.

Figure 9 shows a TEM image of a low-k film formed on the sidewall of the gap using the method.

Referring to Figure 9, a silicon oxide film is conformally formed on the sidewalls of the gap by PEALD and then subjected to a post-processing step. The step coverage between the top and bottom surfaces is about 94%, and a k value of 3.42 is obtained, meeting the target range.

Table 2 shows the dielectric constant (k value) of silicon oxide films by different processing steps.

Dielectric constant (k value) of silicon oxide film Post-processing conditions k value Condition A Upon deposition (no post-processing) >5.0 Condition B Heat treatment (390℃, 30 minutes) >5.0 Condition C Heat treatment and plasma treatment (390℃, Ar plasma, 400W, 10 minutes) About 3.5

As shown in Table 2, Condition A (as deposition, no post-treatment) exhibits high k values (>5.0). The high k value of Condition A can be attributed to the moisture present in the film network structure (Figures 6 and 7) since the film is formed at low temperature and low RF power. Condition B (heat treatment only) also results in high k values (>5.0). The high k value of Condition B can be attributed to the moisture still remaining in the silicon oxide network structure (Figures 6 and 7).

Condition C (heat treatment and plasma treatment) results in a k value (approximately 3.5) that satisfies the target k value (less than 3.5). That is, performing heat treatment and plasma treatment simultaneously can facilitate removing moisture from the membrane network structure and lowering the k value to the target value. In other embodiments, UV or VUV (vacuum UV) treatment can be performed instead of plasma treatment.

Table 3 shows process conditions for forming a low-k silicon oxide film according to the present disclosure.

Process conditions for forming low-k silicon oxide films Process parameters Deposition stage Post-processing step Temperature (℃) Susceptor 20 to 100 (preferably 35 to 90) 300 to 500 (preferably 350 to 450) Shower head 30 to 100 (preferably 35 to 90) 100 to 200 (preferably 120 to 180) reactor wall 30 to 100 (preferably 35 to 90) 100 to 200 (preferably 120 to 180) Gas flow rate (sccm) Source carrier Ar 50 to 5,000 (preferably 70 to 3,000) - Fuzzy Ar 1,000 to 6,000 (preferably 2,000 to 5,000) 1,000 to 6,000 (preferably 2,000 to 5,000) Reactant (O2) 50 to 200 (preferably 70 to 180) - Hydrogen (H2) 50 to 3,000 (preferably 70 to 2,000) - Process time per step (seconds) First precursor supply 0.1 to 1.0 (preferably 0.2 to 0.8) - Second precursor supply 0.1 to 1.0 (preferably 0.2 to 0.8) - fudge 0.1 to 1.0 (preferably 0.2 to 0.8) - RF on 0.05 to 1.0 (preferably 0.1 to 0.8) - Post-processing - 300 to 1,200 (preferably 400 to 1,000) RF Power (W) 30 to 200 (preferably 40 to 150) 200 to 600 (preferably 300 to 500) Process pressure (Pa) 200 to 500 (preferably 250 to 450) 200 to 500 (preferably 250 to 450) First precursor Amine group containing organosilane - Second precursor Aminosilane -

Substrate processing according to the present disclosure can be performed in-situ or ex-situ. In the case of an in-situ process, deposition and post-treatment can be performed in one reactor. In the case of an ex-situ process, deposition can be performed in one reactor. After deposition is completed, the substrate can be transferred to another reactor, and post-treatment can be performed therein.

FIG. 10 illustrates a TSV process to which an embodiment of the present disclosure may be applied. As illustrated in FIG. 10, a substrate processing method according to an embodiment of the present disclosure may include steps of forming a barrier film, such as Ta/TaN, on a silicon oxide film, filling a recess structure with a conductive film, and planarizing the substrate.

In FIG. 10A, a substrate (1) having a recess (2) is provided. The recess may be a gap or a via.

In FIG. 10B, a liner (3) can be formed along the surface of the recess (2). The liner (3) can be a low-k film formed by the method of the present disclosure.

In FIG. 10C, a barrier film (4) can be formed on the liner (3). The barrier film can prevent a conductive element of a conductive film (5) formed in a next step from diffusing through the liner (3) to the substrate (1). The barrier film (4) can include at least one of Ta, TaN, Ta/TaN, and TiN or a mixture thereof. The barrier film can be formed by at least one of ALD, PEALD, CVD, or PECVD.

In FIG. 10D, a conductive film (5) can fill the recess (2). The conductive film (5) can include at least one of copper, tungsten, and poly-silicon or a mixture thereof. The conductive film (5) can be formed by at least one of electrochemical deposition or CVD.

In FIG. 10E, planarization can be performed. In the planarization, the substrate (1) can be planarized by t1 from the top and polished by t2 from the opposite side of the substrate (i.e., the bottom of the substrate). Although not shown in FIG. 10, in a subsequent process, a plurality of planarized substrates can be stacked through FIG. 10A to FIG. 10E, thus forming a long and deep recess and a conductive film filling therein.

It should be understood that the configurations and/or approaches described herein are exemplary in nature and that many variations are possible, and therefore these specific implementations or examples should not be considered in a limiting sense. The specific routines or methods described herein may represent one or more of any of the processing strategies. Accordingly, various operations depicted may be performed in the sequence depicted, in a different sequence, or in some cases omitted.

The subject matter of the present disclosure includes all novel and non-obvious combinations and subcombinations of the various processes, systems, and configurations, and other features, functions, operations, and/or characteristics disclosed herein, as well as any and all equivalents.

Claims (25)

A method for forming a film on the wall of a recess of a substrate in a reactor,
A step of supplying a first silicon precursor to the reactor;
a step of supplying a second silicon precursor to the reactor; and
Comprising a step of supplying an oxidizer to the reactor;
The first silicon precursor comprises (1) a reactive group comprising an alkylamine; and (2) a non-reactive group comprising an alkyl group and a hydrogen group;
The second silicon precursor comprises (1) a reactive group comprising an alkylamine; and (2) a non-reactive group comprising a hydrogen group;
A method wherein the above steps are repeated a plurality of times, and a silicon oxide film is formed on the wall of the recess. In the first paragraph,
A method further comprising the step of supplying a hydrogen-containing gas throughout the above steps. In the second paragraph,
A method wherein the hydrogen-containing gas comprises at least one of hydrogen, an acyclic hydrocarbon, or a combination thereof. In the first paragraph,
A method further comprising the step of performing a post-treatment to remove moisture from the silicon oxide film. In paragraph 4,
A method wherein the above post-treatment is performed by heat treatment and at least one of plasma treatment, UV treatment, VUV treatment, or a combination thereof. In paragraph 4,
A method wherein the post-treatment comprises heat treatment and plasma treatment by supplying at least one of argon plasma, helium plasma, hydrogen plasma, or a combination thereof. In Article 6,
A method wherein the plasma is generated by applying RF power of between about 200 W and about 600 W to the reactor in-situ or remotely. In Article 7,
A method wherein the plasma is generated by applying RF power of between about 300 W and about 500 W to the reactor either on-site or remotely. In paragraph 5,
A method wherein the above heat treatment is performed at a temperature between about 300°C and about 500°C. In Article 9,
A method wherein the above heat treatment is performed at a temperature between about 350°C and about 450°C. In paragraph 4,
A method wherein the above step of forming a film and the above post-processing are performed in-situ. In paragraph 4,
A method wherein the step of forming a film and the post-processing are performed ex-situ. In paragraph 4,
A method wherein the dielectric constant of the silicon oxide film is 3.5 or less. In paragraph 4,
A method wherein the film growth rate of the above silicon oxide film is 0.1 nm or more per cycle. In the first paragraph,
A method wherein the first silicon precursor comprises an organosilane-containing amine group. In Article 13,
A method wherein the first silicon precursor comprises at least one of (dimethylamino)trimethylsilane, bis(dimethylamino)dimethylsilane, N,N-dimethyl-2,4,6,8-tetramethyl-cyclotetrasiloxan-2-amine, N,N-diethyl-2,4,6,8-tetramethyl-cyclotetrasiloxan-2-amine, or a combination thereof. In the first paragraph,
A method wherein the second silicon precursor comprises an aminosilane. In the first paragraph,
The second silicon precursor is DSMA, (SiH ₃ ) ₂ NMe; DSEA, (SiH ₃ ) ₂ NEt; DSIPA, (SiH ₃ ) ₂ N(iPr); DSTBA, (SiH ₃ ) ₂ N(tBu); DEAS, SiH ₃ NEt ₂ ; DTBAS, SiH ₃ N(tBu) ₂ ; BDEAS, SiH ₂ (NEt ₂ ) ₂ ; BDMAS, SiH ₂ (NMe ₂ ) ₂ ; BTBAS, SiH ₂ (NHtBu) ₂ ; DIPAS, SiH ₃ N(iPr) ₂ ; 3DMAS, SiH(N(Me) ₂ ) ₃ ; BEMAS, SiH ₂ [N(Et)(Me)] ₂ ; TEMS, SiH(NEtMe) ₃ ; TIPAS, SiH(NHiPr) ₃ ; A method comprising at least one of BDIPADS, (N(iPr) ₂ )SiH ₂ -SiH ₂ (N(iPr) ₂ ); BDEADS, (NEt ₂ )SiH ₂ -SiH ₂ (NEt ₂ ); BDPADS, (NPr ₂ )SiH ₂ -SiH ₂ (NPr ₂ ), or a combination thereof. In the first paragraph,
A method wherein the oxidizing agent comprises at least one of oxygen plasma, CO ₂ plasma, N ₂ O plasma, ozone, or a combination thereof. In Article 17,
A method wherein the plasma is generated by applying RF power between about 30 W and about 200 W to the reactor either on-site or remotely. In Article 20,
A method wherein the plasma is generated by applying RF power between about 40 W and about 150 W to the reactor either on-site or remotely. In the first paragraph,
A method wherein the above method is performed at a temperature between about 20°C and about 100°C. In the first paragraph,
A method wherein the above method is performed at a temperature between about 35°C and about 90°C. In the first paragraph,
A method wherein the surface of the above recess comprises a hydroxyl group (-OH) and an alkyl group. In the first paragraph,
A step of forming a barrier film on the silicon oxide film;
A step of filling the above recess with a conductive film; and
Further comprising a step of flattening the substrate from the top of the substrate,
The barrier layer comprises at least one of Ta, TaN, Ta/TaN, TiN, or a mixture thereof;
A method wherein the conductive film comprises at least one of copper, tungsten, poly-silicon, or a mixture thereof.